


There is Grey Between the Lines

by ParadoxicallySpeaking



Series: I'll be your guide so you can see the other side [1]
Category: The Flash (TV 2014)
Genre: (go for poly E2 Iris if that what you want!), At the start at least, Barry and Iris are really close, Detective Iris West is better than all of us, Enemies to Lovers, F/F, I'll be over here ignoring the fact that Zoom probably killed Killer Frost, Iris and Caitlin have worked together but they still sort of hate each other, KF flirts to tease Iris but then her feelings get in the way, Killer Frost is a little shit, breaking your super criminal gf out of prison, but its not necessarily romantic, if that doesn't interest you nothing will, unless you want to read it that way
Language: English
Status: Completed
Published: 2016-04-13
Updated: 2016-04-13
Packaged: 2018-05-27 03:17:17
Rating: Teen And Up Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 4,056
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/6267400
Author URL: https://archiveofourown.org/users/ParadoxicallySpeaking/pseuds/ParadoxicallySpeaking
Summary: <blockquote class="userstuff">
              <p>Killer Frost tilted her head sideways. "You just won't quit," her lips spread into a smirk. "Will you, Detective West?"<br/>Iris' lips tugged at a dry smile she pushed down. "Neither will you. Zoom nearly kills you for turning against him," she shakes her head in mild disbelief. "And you're still committing crime."<br/>She made a small mock bow, keeping her eyes locked with Iris' all the time. "What can I say? It's my talent."<br/></p>
            </blockquote>





	There is Grey Between the Lines

**Author's Note:**

> Starts some time after Zoom has been defeated, and spans about 4 months.

"You." Iris' voice was venomous and direct. "How did you escape from Zoom?"

Killer Frost held her hand to her chest and pouted. "You wound me, Detective. I thought we bonded!"

"I thought you would be dead," Iris held up her gun, unwavering and steely.

Frost raised an eyebrow. "I'm detecting some remaining tension between us-"

"You killed my father, you evil, cold-hearted bitch!" Iris squared her shoulders. Other than her outburst she was not going to let her emotions rule her. She would not let her hand wobble all over the place like Lawton's.

The blonde tilted her head sideways. "You just won't quit," her lips spread into a smirk. "Will you, Detective West?"

Iris' lips tugged at a dry smile she pushed down. "Neither will you. Zoom nearly kills you for turning against him," she shakes her head in mild disbelief. "And you're still committing crime."

She made a small mock bow, keeping her eyes locked with Iris' all the time. "What can I say? It's my talent." She breathed out. "But are you really still going to chase me like a common thief?"

Iris' face dropped, almost as if the other woman had disarmed her with her words and now Iris remembered why she was pointing the gun. "No," she whispered. "Not a common thief. My father is dead," Iris paused to breathe deeply, swallowing the quiver in her voice. She would rule this situation. "Dead because of you."

Iris stepped back in shock as Killer Frost's eyes hardened, throwing her arms out to her sides. "As if you have the monopoly on loss!" She snapped. Then the meta shifted, almost seamlessly becoming more composed. "I didn't help you out of the good of my heart! You saw what Zoom did to my husband!" There was a rumble to her voice that suggested her emotions were nowhere near as controlled as she'd like Iris to believe. Her voice dropped to a husky whisper. "You think I wanted that? That there weren't people I loved and wanted to protect?" She growled. "You think I wasn't terrified of Zoom like everyone else?! Killing people wasn't always my style, but after I got my powers," she looked at her hands and then she was smirking again, voice deep and coarse. "I was just _so good_ at it!" She folded her arms. "I could follow orders, and me and Ronnie were talented at what we did-"

"Killing people." Iris cut in.

Frost ignored her. "Zoom found us valuable. But..."

"You were disposable." Iris finished for her and Frost's face paled, if that were possible. Iris recognised the look behind her eyes. She was remembering the death of her husband. "But none of this is an excuse. I pity a lot of criminals, even you. But you still murdered people in cold blood!" Frost snorted at the unintended pun. "And you admitted to enjoying it. You're still a killer. I'm taking you in."

Killer Frost started taking a few steps forward, and Iris made sure she knew she would shoot. "Killer's in my name, babydoll. Sorry, but," She stopped on the edge of pushing her luck - just far enough away from Iris. "I'm all booked up, let's reschedule this dance for another day." She shot a spike of ice above Iris' head, displacing some of Jitterbug's ceiling tiles. Iris took her shot, but her bullet only grazed Killer Frost's arm. She vanished.

* * *

The next time they met was in Central City Bank. "Still going to shoot me, West?" Frost drawled. "Wouldn't that make you the killer?"

"Depends where I shoot." Iris stepped forwards, sending Lawton some hand signals to secure the parameter and aid any civilians. "You're not dead yet."

"Mm, does that mean you're not going to kill me? Why, haven't we come a long way and we're only on our second date."

Iris frowned. "I never said that. I will kill you if I need to, but I won't play judge, jury, and executioner."

Frost clicked her tongue. "So righteous! Have you never thought about throwing those morals to the wind for once?!"

Gaze narrowing, Iris shook her head. "For my own personal gain? Never." Except she had. Not that she would ever act on it. Not that she'd become like Killer Frost.

"You see, babydoll," Frost was wandering aimlessly around her end of the room, stolen money in hand, giving the impression that she had relaxed her guard. Iris knew better. "I think you're lying." Iris swallowed. "I think you do think about it, about turning against the laws of the kingdom you built in that precinct." She grinned into a CCTV camera, tapping it lightly with her fingernail and watching it frost over. "And I think it scares you."

"You don't know anything about me," Iris walked forwards, stepping just within Frost's boundaries.

She reciprocated the movement, a few steps towards Iris, her heels clicking aginst the floor. "Wrong, Detective," She leaned her upper body forwards, testing the limits of her dance. Would she get the great Detective West to break? "I've done some digging; learnt a lot about you. And you have all my files," A smile. "So don't try to deny you haven't done the same!"

Iris swept Frost's legs out from under her, glaring down at her, gun pointed. "Release the hostages." That was a stone-cold demand. It made the meta shiver, and she was never cold.

"Oh, it must kill you to know you can't just shoot me now! Not to mention, I'm the only one who can free them from my ice without harm so you have to let me go _and_ trust that I won't just kill them." Killer Frost picked herself up. "But I like you, West, so this time you win the hostages." She threw her hands out and the ice retracted from the civilians. Frost kicked them forwards and released two spears of ice from her fingertips. Through the panic, Iris heard "Thanks a million, babydoll!" And could only watch as Frost waved the bundle of dollars and blew her a kiss.

Apparently she managed to slip past Deadshot unseen.

* * *

Iris managed to catch her this time. "I told you I would bring you in." Iris slapped the cuffs on Frost's wrists. "And I always make good on my promises." Iris took the criminal's current burner phone and slipped it into her inside pocket.

"Actually you've caught me plenty of times, this is only the first time you've managed to get me into your government-paid bondage gear." Frost grinned as Iris shoved her forwards. "Can't say I'm surprised that you're into this, Detective! Although," She pouted melodramatically. "I thought we were clear on our dance routine! It'll be no fun in prison!" Grinning, she pushed back against Iris. "Unless this is the next step in our relationship, babydoll! I wouldn't mind that!"

Iris had been ignoring her but rolled her eyes at that. "You wish. I'll enjoy seeing you where you can't hurt anyone else more than you can imagine."

"Ah, I thought we were long past this! It's been _ages_ since I last killed someone!" Iris cut her off by shoving her into the back seat of her car. "It's been fun! It really has. Nice to indulge your kink too," She held her cuffed hands up sheepishly. "Just a shame I get out of them so easily!" Ice creeped along the metal, and Iris' eyes widened as it shattered. "Too bad, I was just getting _so hot_ as well!" She snapped her hands to Iris' collar before the other woman could move, and tugged her down to her lips. She felt Iris' warmth seeping into her skin, and _God_ was it intoxicating. As Iris fell limp, the blonde laid her across the seat of the car, reached into Iris' pocket and drew out her burner phone. She called emergency services, checked that Iris still had a constant pulse and no external signs of frostbite, before dropping the phone and crushing it with her heel. "Till next time, babydoll."

* * *

It wasn't hard for her to work out that Frost had never intended to kill her. She was a detective, and Frost was right, Iris knew her files word for word. She was well aware how lethal her powers are. It must have taken Killer Frost a whole lot of restraint. It took a few days longer, and a google of ambulance response times, to realise Frost had also called for the ambulance herself. When Barry stepped into her hospital room with a teddy bear from an unknown sender, it took her almost no time at all to know who sent it.

Or it was wishful thinking.

(She felt somewhat sick that she wanted it was from her.)

* * *

Iris let the gun hang at her side. She didn't trust Frost yet, of course not. But, Iris was sure she wouldn't try to kill her, it wouldn't make any sense. Iris locked eyes with the blonde, and desperately hoped her face carried the emotions she felt, and that she wasn't staring her down menacingly. "Why..." Iris trailed off, looked away. This was stupid, likely to do more bad than good. How was she meant to convey her feelings in words, to a woman she hates. Used to hate.

"Why what?" Killer Frost was ready to fight, this was the way it always went, right?

Iris paused before shaking her head. "You won't kill me." Frost faltered, tilting her head to the side. There was a slight sneer on her blue lips, as if baiting Iris to test that theory. "You didn't kill me last time," Iris continued. "In fact, I know you saved me."

The blonde cackled. "Whatever makes you say that, Detective!?"

"As you say," Iris walked towards her steadliy, almost as if she was an animal that could spook and run away. "I'm a detective. I know your powers. I should have died. Even if I didn't, a google of the ambulance response times in the area made it easy to work out I would have froze before anyone found me. No, the only way an ambulance couldhave arrived in time is if," she smiled nervously at the other woman. "You called it."

Frost had relaxed, eyes downcast, not quite able to look at the detective.

"I just want-" Iris shook her head. "I need to know why." A beat. "Please," she added in a whisper.

Frost's head rose. "Not now, not here," Cold eyes darted around nervously. "There's a bar by the waterfront. You won't like it, but if you want to know, meet me there two days from now at 9 o'clock." Frost turned to bolt, but spun on her toe after several strides. "Don't bring too much attention to yourself, keep your head down. There'll be people with no qualms about killing you."

* * *

Iris drummed her fingers of her right hand on the table at Jitterbug, nursing her cup of coffee in the left. It was definitely appropriately named, Iris had barely sipped at her coffee, and she was already shaking.

Barry approached just as her eyes were floating over to where her dad used to sing. "Iris, no," He cupped her face in his hand. "I know that face, you're having the worst day ever, right? So I am, and here I thought I could do some really good complaining." He slipped into the seat opposite her and smiled sweetly. "It's unfair we're both having the Worst Day Ever." He laid his hand over hers, drawing her back from where her eyes were drifting once again. "So, what's on your mind?" Something in Barry's sympathetic smile, the touch of his hand, the pause he took, suggested that he was asking if she wanted to leave first.

She shook her head. "I'm so confused, Barry! Nothing makes sense. There's someone I should hate, but I don't anymore! I'm really sympathetic to them and... It makes me feel sick, Barry." She gasped back a few tears, as he picked up a napkin and gently dried her cheeks. "I feel like they've changed, and I feel like I can help, but... I shouldn't want to, right!?" She let out a scratchy, dry laugh. "And that's not even starting that it would be against my job! I'm planning on meeting them tomorrow night and I should turn them in! I should  _want_ to turn them in but I don't! I feel like I'll lose my chance, I-"

Barry got up and hugged her. "You're the strongest woman I've ever met, Iris, I love you, you know that. You've always supported me in everything, so now I'm going to support you with this." He tilted her head so she was looking at him. "I just want you to be happy, Iris, so you can tell me anything and everything, until it all makes sense again. And if this person will make you happy, then I wish you the best of luck." He paused. "The other Barry said that their Caitlin Snow was a wonderful person. There's got to be some of that goodness still in her, and I really you're making Frost a better person." Chuckling, he sat back in his seat. "Don't look so surprised! I did the forensics when she hospitalized you, it wasn't hard to work out she saved you!"

"I still don't know how to feel about all this." The few tears that had escaped during her swell of emotions leaving her eyes slightly red.

"But we'll work it out, you'll work it out, I know you can."

* * *

Frost knew as soon as she saw Iris in the corner that she had made the wrong call. She'd been smart, she was sat there alone, but there was a tenseness in her that betrayed her nerves. She hoped that her appearence would calm the brunette, but that seemed unlikely given their track record.

Iris smiled across the table at her. "You're late. I thought you were worried about the trouble I would get into in here."

Frost quirked an eyebrow. It was no joking matter. This bar was full of some of Central's worst criminals, most with a personal grudge against Detective West. "I thought you wouldn't come."

Iris raised an eyebrow of her own. "So this was you trying to scare me off? Well, unluckily for you, I never stop until I get an answer."

"On a different Earth, you'd make a great journalist."

Iris leant forward, elbows on the table. "So..."

Frost swirled her drink, studying the liquid intensely. "I miss Ronnie."

Iris remembered the words of Other Barry's friend. "Your husband? The one Zoom killed?"

Frost nodded rigidly. "You..." She persed her lips. "I was happy being a thief, you know?" Her eyes focussed in on a spot on the table. "I..." she trailed off. "The first person I killed was an accident. Ronnie looked at me in awe, like I was a force of nature, like this is what I was meant to do." Iris' skin prickled as the temperature around them dropped slightly. "It scared me. I scared me. And then he showed me how to stop feeling."

"I think you're feeling now."

Frost bit her lip. "What do you mean?"

"You care about me." Iris took a sip of her drink. "And by the steadly dropping rate of ice-related crimes, and the no longer existent ice-related homicides," Putting down her glass, Iris met Frost's eyes. "You care about others." She held up a hand to stop any protests before they were even voiced. "At least in some small part." She grinned. "Or you're just trying to impress me."

"You flatter yourself, Detective." Frost grinned. "And why would you want a _dangerous criminal_ trying to impress you anyway?"

"It'd make my job far easier."

Frost smiled, this strange comradery was...warm.

A crash and the two women stiffened. There was a scuffle behind them. Someone yelling something about money. Then the unmistakable sound of a body being thrown into a table, and glass shattering. Killer Frost blocked it out. The best way to stay out of it, is to pretend nothing is wrong. Unfortunately, Iris didn't get that memo.

Ugh. There was just too much good in her.

She made to stand up and grab her gun, but Frost grabbed her hand and pulled her down. "You get involved and they'll hurt you. And I may not kill anymore but I've still got a reputation to maintain. Either of us get made by your heroics, and they'll slit both our throats." She withdrew her hand and looked into her eyes. "I'm sorry, Iris. I can't watch you die. It'll blow over soon. Then, we'll leave without bringing too much attention to ourselves."

Frost breathed a silent sigh of relief when she was right. It was over quickly, and with minimal damage. Iris was still tense, drumming her fingers on the table. Frost tossed some money on the table to pay for her and Iris' drinks, before leading her out through the crowd.

"You never did give me that answer."

Frost smiled at her. "Maybe it's so I have a reason to meet you on friendly terms again."

Iris touched her shoulder, meeting her eyes. "Keep out of trouble and I might give you one, one day."

"Maybe next time, babydoll."

Smiling, Iris turned to leave.

* * *

 

"You have no idea how much trouble I'll get in if anyone ever finds out I took this for you." Barry placed a small device in Iris' hand, before cupping it between his. "This is the remote control for the meta-collars. I have a feeling why you would want this, and if you ever need to use it, please be careful. She's not worth risking your job over, so never use it where your collegues could see, promise me. Even if one of the other detectives catches her - I can't break you both out of Iron Heights." His eyes sparkled with a small smile. "I trust you, Iris, but promise me you'll stay safe."

As she reached up and wrapped her arms around his neck in thanks, she nodded her head. "Always."

* * *

It's an odd day when _Deadshot_ pulls in one of the most notorious criminals in Central City's history. In handcuffs. Apparently Killer Frost had tried to enter the building dressed in civilian clothes, and then put up no resistance when caught.

Iris' eyes met with Frost's, and the blonde grinned as she was sat down in front of her for questioning, a metapower-dampening collar around her neck. "I don't know why I need the collar, I didn't even fight that useless partner of yours. Do you know how hard it was to feign feeling threatened by a gun literally pointing everywhere apart from at me? Has he ever shot anything?"

"Cut to the chase, Caitlin," Iris grinned internally at the way Frost's nose scrunched up at the use of her real name. "Why are you here?"

"I thought you deserved your answer." Iris' eyes widened. She acted quickly, her hand under the table.

Frost jumped out of her seat, ripping a now deactivated collar from her neck. As the other detectives scrambled to the door, Frost sealed it shut with a layer of ice. She froze and shattered the CCTV camera before turning to Iris, a twisted smile on her lips. The brunette's heart was racing, earthy night-like eyes wide and pupils blown. This was her plan all along, Iris was sure she had control over the situation but her damn feelings! Why did she turn the collar off? Iris would die here, having been played for a fool by a murderer.

Blue lips stretched into a grin. "Two days from now, we've got a dinner reservation at your favourite restaurant. Don't pass out on me, Detective! It'd be a real shame if we couldn't make it."

Iris placed her forehead in her hands, trying to calm her quickened breathing. "Holy shit, seriously, couldn't you have been less convincing! That was cruel, _Caitlin._ " She drawled the name, watching Frost's eyes roll.

"Guess I deserved that, huh?"

"You don't say!" Iris paused. "How do you know my favourite restaurant anyway?"

"I stalked your Instagram, it's no big deal."

Iris persed her lips. "Uh-huh, and how are we going to get out of this?"

"The ice won't hold your underlings for long, and you'll be holding a gun over my subdued body when they get in. Punch me, I deserve it!" She grinned.

Well, Iris always was one to follow orders.

* * *

 Iris couldn't justify it really. This whole thing was insane.

She wasn't even meant to be here right now, and what if something happened! She would technically be releasing a dangerous criminal out onto the streets. But then she really believed Frost was changing, and Barry seemed to as well, although Barry had always seen the best in the worst of people.

She'd covered her tracks, made it look like a temporary fault, that lead to some of the cells opening.

And if there was a malfunction in the metahuman wing of Iron Heights that offered Killer Frost the opportunity to escape at the same day Iris left work early for a date, then none of her co-workers even had any suspicions.

* * *

Iris was taken aback at how different Frost looked. Not so different that Iris couldn't spot her, knowing where she'd be, but she couldn't be picked out of the crowd by someone who didn't know what to look for.

Her hair was slightly darker - Iris spent most of the evening trying to decipher whether it was a wig, or due to her subduing her powers - and was twisted up to lie at the nape of her neck, secured by a jeweled hairpin that Iris had a feeling wasn't just money-can't-buy, but money-didn't-buy.

As Frost stood to greet Iris and pull out her chair, she revealed her dress, a sea-green evening grown with a sweetheart neckline, and Iris caught herself staring for a second. Frost's eyes sweeped appreciatively over Iris' long, sleek red dress in much the same way. Before Iris sat, she placed a napkin over her skin and kissed her cheek with pinkish lips. She smirked and, winking, whispered, "Can't have you getting _chills_."

"So," Iris began once they were sat and their meals had been ordered. "My explanation? I've been waiting a long time for this."

"I miss Ronnie," Frost whispered. "As simple as that. You were a good distraction for a while, someone who was so determined to stop me, but neither of us could quite get at the other. But then I realised," she laughed. "I was getting rather fond of you, Iris."

Iris smiled. "So then after you gave me the kiss of near-death..."

"It became real. I already knew I couldn't kill you, but after that, I realised I couldn't kill anyone. I didn't want to. It was...liberating to say the least." She paused to eat. "Ronnie and you, you're so different but, I think you're good for me." Iris smiled at her so sincerely, she couldn't stop herself smiling back if she wanted to. "I think this is what I need."

"Normality?" Iris laughed. "Because nothing in our relationship has been normal," she lowered her voice. "I just broke you out of Iron Heights."

"I never said normality," she grinned. "I need you. Your warmth, your kindness, all your flaws. Could we really make this work? Any kind of relationship between us?"

"I could lose my job, you could get locked away in Iron Heights for a long time..." Iris paused and she bit her bottom lip. "But you know what, babydoll, I want to try." There was something about the way the name rolled of her tongue, she could see why Frost loved calling her it.

Frost beamed as Iris placed a kiss on her pale knuckles.

"I'm glad you helped us save Other Barry from Zoom. Without that, I don't think I could've ever given you a chance. It would have been a shame to never get to know Caitlin Snow." When Frost made a happy sound into agreement, Iris tilted her head. "Woah, I can call you that?"

"I guess so," Caitlin looked up at her, a small happy smile on her lips. "Maybe you thawed me out."

**Author's Note:**

> Title from the song Leave A Trace by CHVRCHES.  
> In the first draft I broke up Barry and Iris, but my westallen heart couldn't bear to do so, so it's just not mentioned.  
> I've been writing this on-and-off for a couple of months - after 2x13 I absolutely had to write this, but after 2x14 I had to change a lot of it but I hope you enjoyed my labour of love.  
> I'll be writing some other Earth-2 based fics (not necessarily Iris/Caitlin) when inspiration strikes.  
> I also might write a follow up to this, if anyone wants, as I'm sad I never gave them a real happy ending.


End file.
